Metallurgical processing installation

ABSTRACT

Metallurgical processing installation comprising a metallurgical vessel lined internally with water cooled panels. A vessel access tower ( 61 ) fits around vessel ( 11 ) and supports a coolant flow system ( 62 ) to provide for flow of cooling water to and from the cooling panels within the vessel through water inlet and outlet connections ( 42,43 ) distributed around the exterior of the vessel. Coolant flow system ( 62 ) includes large diameter water supply and return pipes ( 66,67 ) mounted on an upper part of the tower ( 61 ) to extend around the upper end of vessel ( 11 ), a first series of vertical dropper pipes ( 68 ) of relatively small diameter connected to the main water supply pipe  66  and extending downwardly to connections with the water inlet connectors for respecting cooling panels of the vessel and a second series of smaller diameter vertical pipes ( 69 ) connected at their upper ends to the main return pipe ( 67 ) and at their lower ends to undivided outlet connectors for the cooling panels in the vessel.

TECHNICAL FIELD

The present invention relates to metallurgical processing installationsin which metallurgical processes are performed within metallurgicalvessels. The invention has particular but not exclusive application toinstallations used for performing direct smelting to produce moltenmetal in pure or alloy form from a metalliferous feed material such asores, partly reduced ores and metal-containing waste streams.

A known direct smelting process, which relies principally on a moltenmetal layer as a reaction medium, and is generally referred to as theHIsmelt process, is described in U.S. Pat. No. 6,267,799 andInternational Patent Publication WO 96/31627 in the name of theapplicant. The HIsmelt process as described in these publicationscomprises:

-   -   (a) forming a bath of molten iron and slag in a vessel;    -   (b) injecting into the bath:        -   (i) a metalliferous feed material, typically metal oxides;            and        -   (ii) a solid carbonaceous material, typically coal, which            acts as a reductant of the metal oxides and a source of            energy; and    -   (c) smelting metalliferous feed material to metal in the metal        layer.

The term “smelting” is herein understood to mean thermal processingwherein chemical reactions that reduce metal oxides take place toproduce liquid metal.

The HIsmelt process also comprises post-combusting reaction gases, suchas CO and H₂ released from the bath, in the space above the bath withoxygen-containing gas and transferring the heat generated by thepost-combustion to the bath to contribute to the thermal energy requiredto smelt the metalliferous feed materials.

The HIsmelt process also comprises forming a transition zone above thenominal quiescent surface of the bath in which there is a favourablemass of ascending and thereafter descending droplets or splashes orstreams of molten metal and/or slag which provide an effective medium totransfer to the bath the thermal energy generated by post-combustingreaction gases above the bath.

In the HIsmelt process the metalliferous feed material and solidcarbonaceous material is injected into the metal layer through a numberof lances/tuyeres which are inclined to the vertical so as to extenddownwardly and inwardly through the side wall of the smelting vessel andinto the lower region of the vessel so as to deliver the solids materialinto the metal layer in the bottom of the vessel. To promote the postcombustion of reaction gases in the upper part of the vessel, a blast ofhot air, which may be oxygen enriched, is injected into the upper regionof the vessel through the downwardly extending hot air injection lance.Off gases resulting from the post-combustion of reaction gases in thevessel are taken away from the upper part of the vessel through anoffgas duct.

The HIsmelt process enables large quantities of molten metal to beproduced by direct smelting in a single compact vessel. This vessel mustfunction as a pressure vessel containing solids, liquids and gases atvery high temperatures throughout a smelting operation which can beextended over a long period. As described in U.S. Pat. No. 6,322,745 andInternational Patent Publication WO 00/01854 in the name of theapplicant the vessel may consist of a steel shell with a hearthcontained therein formed of refractory material having a base and sidesin contact with at least the molten metal and side walls extendingupwardly from the sides of the hearth that are in contact with the slaglayer and the gas continuous space above, with at least part of thoseside walls consisting of water cooled panels. Such panels may be of adouble serpentine shape with rammed or gunned refractory interspersedbetween. Other metallurgical vessels have been provided with internalrefractories and refractory cooling systems. In a conventional ironmaking blast furnace for example, the cooling system generally comprisesa series of cooling staves of robust cast iron construction capable ofwithstanding the forces generated by the large quantities of burdenextending upwardly through the column of the blast furnace. These stavesare only replaced during a reline, during which the blast furnace shutsdown for an extended period. These days the period between relines for ablast furnace which operates continuously can be over twenty years and areline extends over a number of months.

Electric arc furnaces, such as those used for the batch production ofsteel on the other hand, may employ cooling panels which are simplysuspended from a support cage which can be accessed when the lid isremoved and are treated almost like consumables. They can be replacedand/or repaired during other scheduled down times or between heats.

The metallurgical vessel for performing the HIsmelt process presentsunique problems in that the process operates continuously, and thevessel must be closed up as a pressure vessel for long periods,typically of the order of a year or more and then must be quicklyrelined in a short period of time as described in U.S. Pat. No.6,565,798 in the name of the applicant. This requires the installationof internal cooling panels in an area to which there is limited accessand a coolant flow system which enables controlled flow of coolant toand from the individual panels.

DISCLOSURE OF THE INVENTION

The invention provides a metallurgical processing installationcomprising:

-   -   (a) a hollow metallurgical vessel;    -   (b) a plurality of cooling panels forming an internal lining for        at least an upper part of the vessel, each panel having an        internal passage for flow of coolant therethrough;    -   (c) coolant inlet and outlet connectors for the panels at        locations distributed around the exterior of the vessel; and

(d) a coolant flow system for flow of coolant to and from the panelinlet and outlet connectors, which flow system comprises a supply pipeand a return pipe extending generally horizontally at least partiallyaround the vessel, a first series of upright smaller pipes connected tothe main supply pipe and to the panel inlet connectors and a secondseries of upright pipes connected to the return pipe and to the paneloutlet connectors.

The coolant flow system may be supported on a tower structure at leastpartially surrounding the vessel.

The tower structure may be comprised of a structural frame work ofinterconnecting columns and beams and it may have walkways for access tothe vessel and/or the coolant flow system.

The main coolant supply pipe and the return pipe may both be supportedon an upper part of the tower structure and the first and second seriesof smaller cross section pipes may extend downwardly therefrom.

The supply pipe and return pipe may each be of generally U-shapedconfiguration and disposed generally about an upper end of the vessel.

The first and second series of upright pipes may be connected to thepanel inlet and outlet connectors via respective individual inlet andoutlet valves allowing for adjustment of the coolant flow to and fromthe panels individually.

The connections to the panel inlet and outlet connectors may be made byflexible couplings.

The metallurgical vessel may be fitted with a hot gas injection lancefor injecting hot gas downwardly in to an upper part of the vessel,which lance is provided with coolant flow passages, and the towerstructure may also support a gas lance coolant flow system for flow ofcoolant to and from the coolant flow passages of the hot gas injectionlance.

The metallurgical vessel may also be fitted with a series of solidsinjection lances for injection of solids into a lower part of thevessel, which lances are provided with coolant flow passages, and thetower structure may also support a solids lance coolant flow system forflow coolant to and from the coolant flow passages of the solidsinjection lances.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more fully explained, one particularembodiment will be described in some detail with reference to theaccompanying drawings in which:

FIG. 1 is a vertical cross-section through a direct smelting vesselprovided with internal cooling panels;

FIG. 2 is a plan view of the vessel shown in FIG. 1;

FIG. 3 illustrates the arrangement of cooling panels lining a maincylindrical barrel part of the vessel;

FIG. 4 is a development of the cooling panels shown in FIG. 3;

FIG. 5 is a development showing diagrammatically the complete set ofcooling panels fitted to the vessel;

FIG. 6 is an elevation of one of the cooling panels fitted to thecylindrical barrel section of the vessel;

FIG. 7 is a plan of the panel shown in FIG. 7;

FIG. 8 is a cross-section on the line 8-8 in FIG. 6;

FIG. 9 is a front view of the cooling panel illustrated in FIG. 6;

FIG. 10 illustrates a detail of the cooling panel;

FIGS. 11 and 12 illustrate details of the connection of a cooling panelto the vessel shell;

FIG. 13 illustrates a vessel access tower which extends about the directsmelting vessel in a direct smelting plant and which is provided withcoolant flow systems for flow of coolant to and from the cooling panelsof the vessel and to other equipment fitted to the vessel;

FIG. 14 further illustrates the construction of the vessel access tower;

FIG. 15 illustrates the vessel and a part of the coolant flow systems onthe access tower; and

FIG. 16 illustrates the coolant flow systems with the vessel removed;and

FIGS. 17 a and 17 b provide a pictorial representation of the vessel incombination with the access tower and the coolant flows systems

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 and 2 illustrate a direct smelting vessel suitable for operationof the HIsmelt process as described in U.S. Pat. No. 6,267,799 andInternational Patent Publication WO 96/31627. The metallurgical vesselis denoted generally as 11 and has a hearth 12 which includes a base 13and sides 14 formed of refractory bricks, a forehearth 15 fordischarging molten metal continuously and a tap hole 16 for dischargingmolten slag.

The base of the vessel is fixed to the bottom end of an outer vesselshell 17 made of steel and comprising a cylindrical main barrel section18, an upwardly and inwardly tapering roof section 19, and an uppercylindrical section 21 and lid section 22 defining an offgas chamber 26.Upper cylindrical section 21 is provided with a large diameter outlet 23for offgases and the lid 22 has an opening 24 in which to mount adownwardly extending gas injection lance for delivering a hot air blastinto the upper region of the vessel. The hot gas injection lance isinternally water cooled, being provided with inner and outer annularcoolant flow passages for inward and outward flow of cooling water. Moreparticularly, this lance may be of the general construction disclosed inU.S. Pat. No. 6,440,356.

The main cylindrical section 18 of the shell has eight circumferentiallyspaced tubular mountings 25 through which to extend solids injectionlances for injecting iron ore, carbonaceous material, and fluxes intothe bottom part of the vessel. The solids injection lances are alsointernally water cooled, being provided with inner and outer annularcoolant flow passages for inward and return flows of cooling water. Moreparticularly, the solids injection lances may be of the generalconstruction disclosed in U.S. Pat. No. 6,398,842.

In use the vessel contains a molten bath of iron and slag and the upperpart of the vessel must contain hot gases under high pressure andextremely high temperatures of the order of 1200° C. The vessel istherefore required to operate as a pressure vessel over long periods andit must be of robust construction and completely sealed. Access to theinterior of the vessel is extremely limited, access essentially beinglimited on shut down through lid opening 24 and reline access doors 27.

Vessel shell 11 is internally lined with a set of 107 individual coolingpanels through which cooling water can be circulated and these coolingpanels are encased in refractory material to provide a water cooledinternal refractory lining for the vessel above the smelting zone. It isimportant that the refractory lining be virtually continuous and thatall of the refractory material be subject to cooling as uncooledrefractory will be rapidly eroded. The panels are formed and attached tothe shell in such a way that they can be installed internally within theshell 11 and can be removed and replaced individually on shut downwithout interfering with the integrity of the shell.

The cooling panels consist of a set of forty-eight panels 31 lining themain cylindrical barrel section 18 of the shell and a set of sixteenpanels 32 lining the tapering roof section 19. A first set of fourpanels 33 line a lower part of the off-gas chamber 26 immediately abovethe tapering roof section 19. Twenty panels 34 line the section of theoff-gas chamber 26 above the first set of four panels 33. Eleven panels35 line the lid 22 and eight panels 40 line the outlet 23.

The panels of the off-gas chamber and the lowest row of panels in thebarrel section are formed from a single layer of pipes, whereas theremaining panels of the barrel section 31 and also of the tapering roofsection 19 are formed from a double layer of pipes, disposed one infront of the other relative to the vessel shell 17. The lowest row ofpanels 31 in the barrel section are located behind the refractory of thehearth and are closest to the molten metal. In the event of significantrefractory erosion or spalling there is potential for these panels tocontact molten metal and therefore are preferably constructed of copper.The remaining panels in the barrel section and also the off-gas chamber26 may be constructed of steel.

The construction of panels 31 and the manner in which they are mountedon the main cylindrical barrel 18 of the vessel shell is illustrated inFIGS. 6-12. As shown in FIGS. 3, 4 and 5, these panels are disposed in 6vertically spaced tiers of arcuate panels spaced circumferentially ofthe vessel, there being eight individual panels 31 in each tier. Eachpanel 31 is comprised of a coolant flow tube 36 bent to form inner andouter panel sections 37, 38 of zigzag formation. The inner and outerpanel sections 37, 38 are also vertically off-set such that thehorizontal pipe segments of one panel section are located intermediatethe horizontal pipe segments of the other panel section. Coolant inletand outlet tubular connectors 42 extend from the inner panel section atpreferably one end of each panel, though they may also extend from othersections of, or locations on, the panel.

Panels 31 are of elongate arcuate formation having greater length thanheight and with a curvature to match the curvature of the maincylindrical barrel section 18 of the shell. As may be seen from FIGS. 3& 4 a series of apertures 55 are formed within the set of barrel panels31. These apertures 55 align with the circumferentially spaced tubularmountings 25 and operate to provide clearance sufficient for solidsinjection lances to penetrate into the interior of the vessel 11.Typically the apertures are shaped so as to accommodate generallycylindrical solids injection lances that extend through the vessel shell17 and the panels 31 so as to form an angle to a vertical planetangential to the vessel shell 17 at the centre point of thepenetration. The apertures 55 are formed by alignment of two or morepanels having, recesses formed along an edge. The recesses may be alongvertical or horizontal edges or may be at one or more corners. Thetubular mountings 25 are spaced circumferentially of the vessel at acommon height. The panels that form apertures 55 are of a lengthcorresponding to the circumferential distance between tubular mountings25 such that typically the centre line of each lance is aligned with thevertical edge of two or more adjacent panels. This arrangement resultsin the panels in the region of the solids injection lances havingrecesses along both vertical edges. These recesses may extend to theupper or lower corner of the panel.

A set of four mounting pins 43 are connected to the zigzag tubularformation of the outer panel section 38 by means of connector straps 44so as to project laterally outwardly from the panel. Each connectorstrap 44 is fastened at its ends to adjacent tube segments of the innerpanel section and extends between its ends outwardly across a tubesegment of the outer panel section in the manner shown most clearly inFIG. 10. The connector straps 44 are generally V-shaped with the root ofthe V-shape curved to fit snugly about the tube segment of the outerpanel section. The pins 43 are welded to the connector straps so as toextend outwardly from the roots of the V-shapes. The connecting strapsserve to brace the panels by holding the tube segments securely inspaced apart relationship at multiple locations distributed throughoutthe panels, resulting in a strong but flexible panel construction.

The mounting pins 43 are extended through openings 45 in the shell 17and tubular protrusions 46 surrounding the openings 45 and protrudingoutwardly from the shell 17. The ends of pins 43 project beyond theflanges 57 located at the outer ends of the tubular protrusions 46. Thepins 43 are connected to the flanges 57 by welding annular metal discs47 to the pins 43 and the flanges 57 thus forming connections exteriorlyof the shell in a way which seals the openings 45.

In similar fashion the inlet and outlet connectors 42 for the panelproject outwardly through openings 48 in the shell 17 and through andbeyond tubular protrusions 49 surrounding those openings and protrudingoutwardly from the shell and connections are made by welding annulardiscs 51, between the connectors 42 and flanges 59 located on theextremity of the protrusions 49. In this way, each panel 31 is mountedon the shell through the four pins 43 and the coolant connectors 42 atindividual connections exteriorly of the shell. The pins and coolantconnectors are a clearance fit within the tubular protrusions tubes 46,49. The protrusions 46, 49, the flanges 57, 59, the discs 47 and thepins 43 are rigid and have sufficient strength to support the load ofthe panels in a cantilevered manner from the extremity of theprotrusions when the panels are operational and hence filled withcooling water and encased in refractory.

The panels 31 are removed by grinding the weld between the pins 43 andthe flanges 57 and between the coolant connectors 42 and the flanges 59.In this way the panels are readily removed. The flanges 57, 59 may alsobe removed by grinding before replacement panels are installed. Thismethod allows the panels to be removed with limited damage to theflanges 57, 59, the protrusions 46, 49 and hence the vessel 11.

The pins 43 and the coolant inlet and outlet connectors 42 are orientedso as to project laterally outwardly from the panel in parallelrelationship to one another and so as to be parallel with a centralplane extended laterally through the panel radially of the vessel sothat the panel can be inserted and removed by bodily movement of thepanel inwardly or outwardly of the cylindrical barrel of the vessel.

The gaps 53 between the circumferentially spaced panel 31 must besufficient to enable the trailing outer edges of a panel being removedto clear the inner edges of the adjacent panels when the panel to beremoved is withdrawn inwardly along the direction of the pins 46 andconnectors 42. The size of the gaps required is dependant on the lengthof the arcuate panels and therefore the number of panels extending thecircumference of the barrel section 18. In the illustrated embodimentthere are eight circumferentially spaced panels in each of the six tiersof panels 31. It has been found that this allows minimal gaps betweenthe panels and ensures proper cooling of refractory material at thegaps. Generally for satisfactory cooling it is necessary to divide eachtier into at least six circumferentially spaced panels. Additionally,the arcuate length of an outer panel section may be less than thearcuate length of an inner panel section. Such an arrangement allows thegap 53 between the inner panel section of adjacent panels to beminimised compared with an arrangement where the outer panels sectionand inner panel section are of the same length.

Refractory retainer pins 50 are butt welded to the coolant tubes ofpanels 31 so as to project inwardly from the panels and act as anchorsfor the refractory material sprayed out the panels. Pins 50 may bearranged in groups of these pins radiating outwardly from the respectivetube and arranged at regular spacing along the tube throughout thepanel.

The panels 33 and 34, being fitted to cylindrically curved sections ofthe vessel, are formed and mounted in the same fashion as the panels 31as described above, but some of the panels 34 are shaped in the mannershown in FIG. 5 so as to fit around the offgas outlet 23.

The panels 32 and 35, being fitted to tapered sections of the shell, aregenerally conically curved in the manner shown in the illustrateddevelopment of FIG. 5 except for this variance in shape. However, thesepanels are also formed and mounted to the shell in similar fashion tothe panels 31, each being fitted with mounting pins projecting laterallyoutwardly from the panel and a pair of inlet/outlet coolant connectorsat opposite ends of the panels, the pins and connectors being extendedthrough openings in the shell and connected to tubes projectinglaterally outwardly from the shell to form connections exteriorly of theshell which seal the openings and provide a secure mounting for thepanels while permitting some freedom of movement of the panels.

FIGS. 13 to 16, together with FIGS. 17 a and 17 b illustrate a vesselaccess tower 61 designed to fit around the vessel 11 and fitted with acoolant flow system 62 to provide for flow of cooling water to and fromthe cooling panels 31, 32, 33, 34 and 35 within the vessel and twoseparate coolant flow systems 81, 82 for flow of cooling water to thecoolant flow passage of the hot gas injection lance at the upper end ofthe vessel and to the coolant flow passageway of the solids injectionlances spaced circumferentially around the vessel.

Tower 61 is formed in three modules 61A, 61B and 61C which are installedone on top of the other and welded together on installation at thedirect smelting plant site. The tower is comprised of a structuralframework of columns 63 and beams 64 which carry the coolant flowsystems 62, 81 and 82 and walkways 65 providing access to the vessel andthe coolant flow systems.

The coolant flow system 62 includes water supply and return pipingcomprising large diameter main supply and return pipes 66, 67 mounted onan upper part of tower 61 to extend around the upper end of vessel 11, afirst series of vertical dropper pipes 68 of relatively small diameterconnected to the main water supply pipe 66 and extending downwardly toconnections with the water inlet connectors for the respective coolingpanels of the vessel, and a second series of smaller diameter verticalpipes 69 connected at their upper ends to the main return pipe 67 and attheir lower ends to individual outlet connectors for the cooling panelsin the vessel. Thus the vertical pipes 68 provide for separate flows ofwater from the main supply pipe to individual panels and the pipes 69provide for independent return flow of water from the outlets of theindividual panels. The lower ends of the vertical pipes 68, 69 areconnected to the respective panel inlet and outlet connectors viahorizontal pipe ends which extend inwardly to the respective connectorsand are connected to them via flexible couplings.

The vertical pipes 68 supplying individual water flows to the panels areprovided with individual flow control valves 71 and the vertical pipes61 providing individual return flows from the panels are provided withindividual flow control valves 72 so that both the input and outputflows of each panel of each cooling panel can be adjusted. This allowsfor fine tuning of the flows through all of the panels and control ofcooling throughout the vessel.

The vertical water flow pipes 68, 69 are arranged in adjacent pairs in asheet-like array around the tower 61 and the flow control valves 71, 72are grouped in arrays extending generally horizontally around the towerin the vicinity of horizontal walkways on the tower so that they arereadily accessible by walking around the walkways. The valves arearranged sequentially around the vessel in the same order as therespective cooling panels to which they relate so that the relationshipbetween the valves and the related part of the vessel is readilyapparent.

Coolant flow system 81 provides for flow of water to and from thecoolant flow passageway the hot gas injection lance at the upper end ofthe vessel. As seen in FIGS. 15 and 16, coolant flow system 81 includesmain supply and return pipes 83, 84 mounted on an upper part of tower 61and which are connected by smaller branch pipes 85 to respectiveconnections on the hot air injection lance assembly 86.

Coolant flow system 82 provides for flow of water to and from thecoolant flow passage of the solids injection lances spacedcircumferentially around the vessel. It may also provide cooling waterfor cooling the slag notch of the vessel. As seen in FIGS. 15 and 16,coolant flow system 82, comprises main supply and return pipes 87, 88which are connected by branch pipes to the respective connectors on thesolids injection lances and to cooling water passageways at the slagnotch.

FIGS. 17 a and 17 b provide a pictorial representation of vessel 11 incombination with the access tower 61 and the coolant flow systems 62, 81and 82. In particular, off-gas chamber 26, roof section 19 and an upperportion of barrel section 18 of vessel 11 may be seen along with aportion of the hot gas injection lance and a hot gas supply main 100,that supplies hot gas to the hot gas injection lance.

The access tower 61 comprises an inner periphery that is locatedadjacent the vessel 11 and an external periphery that is laterallydisplaced from the inner periphery. A number of walkways 65 extendbetween the inner periphery and the external periphery and providepersonnel with access to the vessel 11, equipment located on the vessel11, the coolant flow systems 61 and 82 and flow control valves 71 & 72.Additional walkways are provided above the roof section 19 of the vesseland provide access to the hot gas injection lance, its associatedcooling system 82 and the hot gas supply main 100.

The walkways 65 extending between the inner and outer peripheries of theaccess tower 61 include an off-gas chamber control and monitoringwalkway 65 a, a barrel control and monitoring walkway 65 b and a lancecontrol and monitoring walkway 65 c. Cooling to the off-gas chamber 26of the vessel 11 is monitored and controlled from the off-gas chambercontrol and monitoring walkway 65 a. Cooling to the barrel section 18 ofthe vessel 11 is monitored and controlled from the barrel control andmonitoring walkway 65 b. Cooling to the lances and ancillary equipmentis controlled from the lance control and monitoring walkway 65 c.

The off-gas chamber monitoring and control walkway 65 a is locatedadjacent the roof section 19 of the off-gas chamber 26. The main supplyand return pipes 66 & 67 are located above both the roof section 19 andthe off-gas chamber control and monitoring walkway 65 a. The barrelcontrol and monitoring walkway 65 b is the walkway immediately below theoff-gas chamber control and monitoring walkway 65 a. The lance controland monitoring walkway 65 c is the walkway immediately below the barrelcontrol and monitoring walkway 65 b. Additional walkways are locatedbelow the lance control and monitoring walkway 65 c, such as a lanceaccess walkway 65 d that allows personnel to access the solids injectionlances along with a cast house floor 65 e and an end tap floor 65 f.

A raw materials conveying region is located adjacent the solidsinjection lances and the inner periphery of the access tower. It extendsbetween the lance control and access walkway 65 c and the barrel controland access walkway 65 b.

Main supply and return pipes 66 and 67 of coolant flow system 62 operateas header pipes and, as detailed above, are located above the roofsection 19 of the vessel 11. Main supply and return pipes 87, 88 ofcoolant flow system 82 also operate as header pipes and are typicallylocated adjacent the inner periphery of access tower 61 around a midsection of off-gas chamber 26, between the barrel control and monitoringwalkway 65 b and the off-gas chamber control and monitoring walkway 65a.

The coolant flow system 62 supplies cooling water to the water cooledpanels depicted in FIG. 5 that are distributed on the shell of thevessel 11 between a lower region of the vessel adjacent the hearth andthe roof section 19 of the vessel 11. The coolant flow system 82supplies cooling water to solids injection lances that supply rawmaterials to the vessel 11 during operation and also to other ancillaryequipment such as a slag notch through which slag is tapped duringoperation. The coolant flow system 62 for the water cooled panelsoperates at a different cooling water pressure to the coolant flowsystem 82 for the solids injection lances and the ancillary equipment.The headers for the coolant flow system 82 for the solids injectionlances and ancillary equipment are located below the headers for thecoolant flow system 62 for the water cooled panels.

Water flow pipes 68, 69 of coolant flow system 62 that extend betweenthe main supply and return pipes 66 & 67 and the water cooled panelsare, at least in part, distributed across the external periphery of theaccess tower. Water flow pipes of the coolant flow system 82 that extendbetween the main supply and return pipes 87 & 88 and the water cooledinjection lances and ancillary equipment are primarily distributedacross the inner periphery of the access tower.

As can be seen from FIG. 5, a typical embodiment provides in the orderof 100 water cooled panels supported by vessel 11. This results in alarge number of coolant flow pipes distributed across the access tower61 between the main supply and return pipes 66 & 67 and the water cooledpanels.

Water flow pipes 68 & 69 are distributed, at least in part, across theexternal periphery of the access tower. In order to connect with thewater cooled panels, the coolant flow pipes 68 & 69 are routed from theexternal periphery to the inner periphery in a staged manner. Forexample, only those water flow pipes that connect to water cooled panelslocated in the upper region of the vessel (such as the off-gas chamber26) extend directly from main supply and return pipes 66 & 67. Theremainder extend across the external periphery of the access tower 61before being routed back to the inner periphery. This reduces overcrowding of pipe work adjacent the inner periphery of the access tower,at least in the vicinity of the upper region of the vessel 11.

The pipes that connect to water cooled panels located on the middle andlower regions of the vessel extend from the main supply and return pipes66 & 67 along the external periphery of the access tower 61. In thisregard they extend across the external periphery substantially parallelto the upper region of the vessel 11 and hence substantially parallel tothe pipes extending along the inner periphery of the access tower 61adjacent the upper region of the vessel and connecting to water cooledpanels located in this upper region. These pipes on the externalperiphery are then routed to the inner periphery from a position on theaccess tower that is in the vicinity of the middle region of the vessel.Pipes connecting to water cooled panels located below the middle sectionof the vessel may also extend along the external periphery of the accesstower, substantially parallel to the upper and middle section of thevessel, and be routed to the inner periphery of the access tower from aposition in the vicinity of the lower region.

Thus the water flow pipes extending to the upper sections of the vessel11 and the water flow pipes extending to the middle and lower sectionsof the vessel 11, extend in a generally parallel manner along the innerand outer periphery of the access tower and are laterally spaced bywalkways, such as the off-gas chamber control and monitoring walkway 65a. This arrangement typically allows that only those pipes that are tobe connected to water cooled panels located in a particular area of thevessel 11 (such as the off-gas chamber 26) are located at the innerperiphery of the access tower in the particular area of concern. Pipesthat extend past this area and that are connected to a lower area of thevessel 11 are located on the external periphery. This arrangement forthe staged routing of pipes to the inner periphery of the access tower61 helps reduce over crowding of coolant flow pipes adjacent the upperareas of the vessel 11 which would otherwise have all or a large portionof the coolant flow pipes extending past their surface if all of thewater flow pipes were routed along the inner periphery of the accesstower.

Typically the pipes are routed in groups from the external periphery tothe inner periphery of the access tower adjacent the underneath surfaceof the walkways. For example, pipes for the upper section of the barrelmay be routed underneath the barrel control and monitoring platform 65b, whereas pipes for a lower section of the vessel may be routedunderneath the lance control and monitoring walkway 65 c, the lanceaccess walkway 65 d and possibly the cast house floor 65 e. This ensuresthe walkways provide clear access for personnel that is substantiallyfree from water supply pipes.

Alternate embodiments may locate an additional set of header pipesbetween the lance access walkway 65 d and the lance control andmonitoring walkway 65 c. The header pipes are raised off of the lanceaccess walkway 65 d toward the under surface of the lance monitoring andcontrol walkway 65 c. These header pipes service the water cooled panelslocated in the lower region in the vessel 11 adjacent the hearth.Typically they service the lower two rows of water cooled panels.

These additional header pipes are located at an external periphery ofthe lance access walkway 65 d and the water flow pipes that extend offof these headers extend vertically to below the lance access walkway 65d and then are routed either underneath the lance access walkway 65 d totheir connection point with a water cooled panel or extend to below thecast house floor from where they are routed to their connection with awater cooled panel. Control valves 71 & 72 are located on the verticalsection of these pipes adjacent the lance access walkway 65 d so thatthe lower rows of the water cooled panels are controlled from a singlelocation.

As detailed above, water flow pipes of the coolant flow system 62 thatextend between the main supply and return pipes 66 & 67 and the watercooled panels are divided into two groups. A first group extendshorizontally from the headers 66 & 67 toward the inner periphery of theaccess tower 61 and then drop vertically, adjacent the inner peripheryof the access tower 61, in order to connect to the water cooled panelslocated on the off-gas chamber 26. A large portion of these pipes extendbelow the off-gas chamber control and monitoring walkway 65 a and arethen routed adjacent the underneath surface of this walkway to alocation aligned with the required water cooled panel. Once aligned, thepipes extend vertically again from the underneath surface of the walkway65 a to the location on the off-gas chamber of the inlet or outlet pipeof the water cooled panel of interest.

Control valves 71 & 72 and other monitoring and control equipment forthe water cooled panels located in the upper region of the vessel aretypically located at a position above walkway 65 a (i.e. on the verticalsections of the water flow pipes servicing the water cooled panels ofthe off-gas chamber). This location of the control valves 71 & 72enables personnel standing on platform 65 a to monitor and control thecooling of the off-gas chamber from a single walkway.

The second group of water flow pipes 68 & 69 of the coolant flow system62 for the water cooled panels extend from the main supply and returnpipes 66 & 67 to the external periphery of the access tower 61. Thissecond group forms a sheet like array of pipes that extends verticallydown at least a part of the external periphery of the access tower 61.In order to connect to the water cooled panels, these pipes also extendbetween the external periphery and the inner periphery of the accesstower 61 in a horizontal manner. In this regard each pipe extendsunderneath one of the various walkways 65 and is routed, adjacent theunderneath surface of the walkway, toward the inner periphery of theaccess tower 61 and is aligned with the cooling panel of interest. Forexample, pipes that are to be connected to an upper section of thebarrel 18 of the vessel typically extend underneath the barrel controland monitoring walkway 65 b and pipes to be connected to a lower sectionof the barrel 18 of the vessel may extend under the lance control andmonitoring walkway 65 c. Underneath the walkways the pipes are routed toa location aligned with the required water cooled panel. Once aligned,the pipes extend vertically again, typically from adjacent theunderneath surface of the walkway to the location on the vessel 11 ofthe inlet or outlet of the water cooled panel of interest.

A typical embodiment has eight lances and one slag notch and so thenumber of water flow pipes distributed from the main supply pipes 87 &88 across the inner periphery of the vessel is substantially less thanthe number of water flow pipes with the water cooled panels.Accordingly, location of the main supply pipes 87 & 88 adjacent theinner periphery of the access tower does not lead to over crowding ofthe surface of the vessel by coolant flow pipes.

The raw materials conveying region is located adjacent the solidsinjection lances. Raw materials conveying apparatus extend laterallythrough the raw materials conveying region, from adjacent the externalperiphery of the access tower to connect with the solids injectionlances adjacent the inner periphery of the access tower.

The water flow pipes for the coolant panels of the vessel adjacent theraw materials conveying region are distributed across the innerperiphery of the access tower. Similarly the water flow pipes for thesolids lances are also distributed across the inner periphery of theaccess tower. Thus the external periphery of the access tower adjacentthe raw materials conveying region is substantially free of water flowpipes. This provides for relatively unimpeded access to the rawmaterials conveying apparatus and the solids injection lances.

The supply and return pipes for any particular piece of water cooledequipment are typically located adjacent each other. This allows thecontrol valves 71, 72 and other control or monitoring devices for eachpiece of water cooled equipment to be located in close proximity to eachother for ease of operation. Where the supply and return pipes extenddown the external periphery of the tower, the control valves 71 & 72 andother control or monitoring equipment are typically located on thevertical section of the pipes adjacent one of the walkways 65. Thisenables the control valves and other monitoring equipment to be locatedon the external periphery of the access tower 61 for access by personnellocated on the walkway of interest. Where the supply and return pipesare associated with main supply and return pipes 87 & 88 for the solidsinjection lances and the ancillary equipment, the control valves andother control or monitoring equipment are located adjacent the innerperiphery of tower 61 on the lance control and monitoring walkway 65 c

This arrangement allows the control valves and other monitoringequipment for the water cooled equipment located in specific regions ofthe vessel (such as the off-gas chamber 26, the barrel 18) or arrangedin specific groups or separate cooling water circuits (such as thesolids injection lances) to be grouped together in close proximity forease of operation. For example, the control valves and other monitoringequipment for the off-gas chamber 26 are located adjacent to and areaccessible from the off-gas control and monitoring platform 65 a. Asthese water flow pipes extend from the main supply and return pipes 66 &67 directly along the inner periphery of the access tower, the controlvalve and other monitoring equipment on the off-gas control andmonitoring platform are located adjacent the inner periphery of theaccess tower 61. The control valves and other monitoring equipment forthe water cooled panels located on the barrel 18 are located adjacent toand are accessible from the barrel control and monitoring platform 65 b.These water flow pipes extend along the external periphery of the accesstower before extending underneath the barrel control and monitoringplatform 65 b (or a platform lower down on the access tower) and thecontrol valves and other monitoring equipment are located adjacent theexternal periphery of the access tower 61. The control valves and othermonitoring equipment for the solids injection lances and other ancillaryequipment are located adjacent to and are accessible from the lancecontrol and monitoring platform 65 c. The water flow pipes for thesolids injection lances and other ancillary equipment are distributedacross the inner periphery of the access tower. Accordingly the controlvalves and other monitoring equipment for solids injection lances andother ancillary equipment are located adjacent the inner periphery ofthe access tower.

Whilst the embodiment detailed above provides control valves and othermonitoring equipment for different regions of the vessel on differentwalkways, it is possible for control valves for different regions to belocated on the same walkway. For example, the control valves andmonitoring equipment for off-gas chamber 26 and barrel 18 may be locatedadjacent the same walkway as these control valves would be located onthe inner periphery and the external periphery respectively.

The illustrated equipment has been advanced by way of example only. Thephysical construction of the vessel and the cooling panels could bevaried as could the detailed construction of the coolant supply systemand the manner in which it is supported about the vessel. It is to beunderstood that such variations can be made without departing from thescope of the appended claims.

1. A metallurgical processing installation comprising: (a) a fixedhollow metallurgical vessel within which to perform direct smelting of ametalliferous feed material to discharge molten metal continuously; (b)a plurality of cooling panels forming an internal lining for at least anupper part of the vessel, each panel having an internal passage for flowof coolant therethrough; (c) coolant inlet and outlet connectors for thepanels at locations distributed around the exterior of the vessel; (d) acoolant flow system for flow of coolant to and from the coolant inletand outlet connectors, which flow system comprises a supply pipe and areturn pipe extending generally horizontally at least partially aroundthe vessel, a first series of upright smaller pipes connected to thesupply pipe and to the coolant inlet connectors, and a second series ofupright pipes connected to the return pipe and to the coolant outletconnectors; and (e) a tower structure at least partially surrounding thevessel on which the coolant flow system is supported.
 2. An installationas claimed in claim 1, wherein the supply pipe and the return pipe areeach of generally U shaped configuration and are disposed generallyabout an upper end of the vessel.
 3. An installation as claimed in claim1, wherein the first and second series of upright pipes are connected tothe coolant inlet and outlet connectors via respective individual inletand outlet valves allowing for adjustment of the coolant flow to andfrom the panels individually.
 4. An installation as claimed in claim 1,wherein the connections to the coolant inlet and outlet connectors aremade by flexible couplings.
 5. An installation as claimed in claim 1,wherein the tower structure is comprised of a structural frame work ofinterconnecting columns and beams and has walkways for access to atleast one of the vessel or the coolant flow system.
 6. An installationas claimed in claim 1, wherein the supply pipe and the return pipe areboth supported on an upper part of the tower structure and the first andsecond series of smaller pipes extend downwardly therefrom.
 7. Aninstallation as claimed in claim 1, wherein the first and second seriesof upright pipes are connected to the coolant inlet and outletconnectors via respective individual inlet and outlet flow controlvalves allowing for adjustment of the coolant flow to and from thepanels individually and the flow control valves are grouped in arraysextending generally horizontally around the tower structure in thevicinity of horizontal walkways on the tower structure so that the flowcontrol valves are accessible by walking around the walkways.
 8. Aninstallation as claimed in claim 7, wherein the flow control valves arearranged sequentially around the vessel in the same order as therespective cooling panels to which the flow control valves relate.
 9. Aninstallation as claimed in claim 7, wherein the first and second seriesof upright pipes are arranged in adjacent pairs in a sheet-like arrayaround the tower structure.
 10. An installation as claimed in any ofclaims 1-4 or 5-9, wherein the metallurgical vessel is fitted with a hotgas injection lance for injecting hot gas downwardly in to an upper partof the vessel, which lance is provided with coolant flow passages, andthe tower structure also supports a gas lance coolant flow system forflow of coolant to and from the coolant flow passages of the hot gasinjection lance.
 11. An installation as claimed in claim 10, wherein thegas lance coolant flow system comprises main supply and return pipesmounted on an upper part of the tower structure and connected by smallerbranch pipes to the coolant flow passages of the hot gas injectionlance.
 12. An installation as claimed in any of claims 1-4 or 5-9,wherein the metallurgical vessel is fitted with a series of solidsinjection lances for injection of solid metalliferous feed material intoa lower part of the vessel, which lances are provided with coolant flowpassages, and the tower structure supports a solids lance coolant flowsystem for flow of coolant to and from the coolant flow passages of thesolids injection lances.
 13. An installation as claimed in claim 12,wherein the solids lance coolant flow system comprises main supply andreturn pipes mounted on the tower structure and branch pipes connectedto the coolant flow passages of the solids injection lances.
 14. Aninstallation as claimed in any of claims 1-4 or 5-9, wherein the towerstructure comprises an inner periphery adjacent the vessel and anexternal periphery laterally displaced from the inner periphery andwherein a first set of upright pipes, comprising a portion of said firstand second series of upright pipes, is distributed along said innerperiphery and a second set of upright pipes, comprising a furtherportion of said first and second series of upright pipes, is distributedabout at least part of the external periphery of the tower structure.15. The installation as claimed in claim 14 further comprising at leastone platform extending between said inner periphery and said externalperiphery and said platform located between a lower region of the vesseland an upper region of the vessel and said platform providing access forpersonnel to the first and second set of upright pipes and wherein saidsecond set of upright pipes extend from said external peripheryunderneath the at least one platform and connect to the coolant inletconnectors and the coolant outlet connectors.
 16. The installation asclaimed in claim 14, further comprising a plurality of platforms locatedat a plurality of levels between a lower region and an upper region ofsaid vessel and individual pipes of said second set of upright pipes mayextend underneath said platforms from the external periphery to therebyconnect with the inlet and outlet connectors of said panels located atvarying heights on said vessel between said lower region and said upperregion.
 17. The installation as claimed in claim 14, wherein the firstset of upright pipes extend along said inner periphery and connect tothe inlet and outlet connectors of said panels located substantially inan upper region of said vessel and said second set may extend along atleast a portion of said external periphery and connect to the inlet andoutlet connectors of said panels located in a substantially lower regionof said vessel.
 18. The installation as claimed in claim 16, whereinpipes of said second set of upright pipes extend from said externalperiphery underneath one or more said platforms.
 19. The installation asclaimed in claim 14, wherein pipes from the second set of upright pipesextend from the external periphery to the inner periphery of the towerstructure adjacent an underneath surface of a first platform and at theinner periphery extend downwardly to the inlet and outlet connectorslocated on said vessel at points below said first platform.
 20. Theinstallation as claimed in claim 19 wherein pipes from the second set ofuprights pipes extend from the external periphery to the inner peripheryof the tower structure adjacent an underneath surface of a secondplatform located below the first platform and at the inner peripheryextend downwardly to the inlet and outlet connectors located on saidvessel at points below said second platform.
 21. An installation asclaimed in any one of claims 7 to 9 wherein: a first set of uprightpipes, comprising a portion of said first and second series of uprightpipes are connected to the inlet and outlet connectors of the panelslocated in a first region of said vessel such that control valves forthe panels located in said first region are located in a first group ofcontrol valves; and a second set of upright pipes, comprising a furtherportion of said first and second series of upright pipes are connectedto the inlet and outlet connectors of the panels located in a secondregion of said vessel such that control valves for the panels located insaid second region are located in a second group of control valves. 22.An installation as claimed in claim 21 wherein the tower structure hasan inner periphery located adjacent said vessel and an externalperiphery laterally displaced from said inner periphery by at least onewalkway providing access for personnel to said tower structure and saidfirst group of control valves and said second group of control valvesare located adjacent said at least one walkway whereby said first groupof control valves and said second group of control valves are accessiblefrom said platform by personnel.
 23. An installation as claimed in claim22 wherein one of said first or second group of control valves arelocated adjacent said inner periphery and the other of said first orsecond group of control valves are located adjacent said externalperiphery.
 24. An installation as claimed in claim 22, furthercomprising at least two walkways located one above the other and one ofsaid first or second group of control valves are located adjacent saidfirst walkway and the other of said first or second group of controlvalves are located adjacent the second walkway.
 25. An installation asclaimed in claim 12, wherein said tower structure comprises an innerperiphery adjacent said vessel and an external periphery laterallydisplaced from said vessel and the solids lance coolant flow system islocated adjacent said inner periphery and branch pipes connected to saidcoolant flow system are distributed across said inner periphery of saidtower structure.
 26. An installation as claimed in claim 12, whereinsaid tower structure comprises a raw materials conveying region adjacentan inner periphery of said tower structure, raw materials conveyingapparatus located in said raw materials conveying region and connectedto said lances and extending laterally away from said vessel toward anexternal periphery of said tower structure, said first and second seriesof said upright pipes distributed about said inner periphery of saidtower structure adjacent said raw materials conveying region.